Texas man charged with the execution-style killings of eight people

A Texas man charged with the execution-style killings of eight people has given a jailhouse interview detailing how he planned and a...

A Texas man charged with the execution-style killings of eight people has given a jailhouse interview detailing how he planned and allegedly came to shoot his victims, including his ex-girlfriend and son.

David Ray Conley III, 48, is charged with three counts of capital murder following the mass-shooting in the Houston-area Harris County home on Saturday night.

During a series of interviews from jail, Conley cried as he explained how he had become 'fed up' with Valerie Jackson, who he had an on-off relationship with over the course of 14 years, as well as their son, Nathaniel, 13, and her children, who he helped raise.

Conley had recently moved out of the house where the killings occurred, and Valerie's ex-husband, Dwayne Jackson - one of the victims and the father of the other five children - had moved back in.

According to ABC 7, Conley told investigators that he planned to kill all eight people, and bought a 9mm handgun online, as well as three clips of ammunition, and six handcuffs.

At 10.30am on Saturday, he parked down the street from the house so he wouldn't be seen.

Valerie Jackson had recently changed the locks on the house, so he got in by breaking a window.

Conley told investigators that he gathered all the victims in the master bedroom.

Some were tied up and others handcuffed to the bed.

He then proceed to shoot all of them, starting with Dwayne Jackson, and then the six children, over the course of the day.

Valerie Jackson was handcuffed to the bed as her husband and her children were murdered in front of her.

Police were called to the house for at least three welfare checks starting from 10.50am, ABC 7 reported, but did not enter the house.

At 8pm, on the fourth welfare check, officers attempted to enter house, but Conley allegedly opened fire.

After a one-hour stand-off, the Harris County Sheriff's Office High Risk Operations Unit and Hostage Negotiation Team negotiated his surrender.